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Display objects using LINQ and SubSonic

I am creating a small project with SubSonic 3.0.0.3 ActiveRecord, and I am having a problem that I seem to be unable to handle.

Here is the LINQ query:

var result = from r in Release.All()
             let i = Install.All().Count(x => x.ReleaseId == r.Id)
             where r.ProductId == productId
             select new ReleaseInfo
             {
                 NumberOfInstalls = i,
                 Release = new Release
                 {
                     Id = r.Id,
                     ProductId = r.ProductId,
                     ReleaseNumber = r.ReleaseNumber,
                     RevisionNumber = r.RevisionNumber,
                     ReleaseDate = r.ReleaseDate,
                     ReleasedBy = r.ReleasedBy
                 }
             };

The ReleaseInfo object is a custom class and looks like this:

public class ReleaseInfo
{
    public Release Release { get; set; }
    public int NumberOfInstalls { get; set; }
}

Release and Install are classes created by SubSonic.

When I make a clock with the result, the Release property is null.

If I make this a simpler result of querying and viewing, the value is not null.

var result = from r in Release.All()
             let i = Install.All().Count(x => x.ReleaseId == r.Id)
             where r.ProductId == productId
             select new Release
             {
                 Id = r.Id,
                 ProductId = r.ProductId,
                 ReleaseNumber = r.ReleaseNumber,
                 RevisionNumber = r.RevisionNumber,
                 ReleaseDate = r.ReleaseDate,
                 ReleasedBy = r.ReleasedBy
             };

Is this a problem with my LINQ query or SubSonic restriction?

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4 answers

, . SubSonic , , : :

: 269 - 298 SubSonic.Linq.Structure.DbQueryProvider

IEnumerable<T> result;
Type type = typeof (T);
//this is so hacky - the issue is that the Projector below uses Expression.Convert, which is a bottleneck
//it about 10x slower than our ToEnumerable. Our ToEnumerable, however, stumbles on Anon types and groupings
//since it doesn't know how to instantiate them (I tried - not smart enough). So we do some trickery here.
    if (type.Name.Contains("AnonymousType") || type.Name.StartsWith("Grouping`") || type.FullName.StartsWith("System.")) {
    var reader = _provider.ExecuteReader(cmd);
    result = Project(reader, query.Projector);
    } else
    {
        using (var reader = _provider.ExecuteReader(cmd))
        {
            //use our reader stuff
            //thanks to Pascal LaCroix for the help here...
            var resultType = typeof (T);
            if (resultType.IsValueType)
            {
                result = reader.ToEnumerableValueType<T>();
            }
            else
            {
                result = reader.ToEnumerable<T>();
            }
        }
    }
    return result;

, SubSonic ToEnumerable datareader , . SQL Query Linq :

SELECT [t0].[Id], [t0].[ProductId], [t0].[ReleaseDate], [t0].[ReleasedBy], [t0].[ReleaseNumber], [t0].[RevisionNumber], [t0].[c0]
FROM (
  SELECT [t1].[Id], [t1].[ProductId], [t1].[ReleaseDate], [t1].[ReleasedBy], [t1].[ReleaseNumber], [t1].[RevisionNumber], (
    SELECT COUNT(*)
    FROM [dbo].[Install] AS t2
    WHERE ([t2].[ReleaseId] = [t1].[Id])
    ) AS c0
  FROM [dbo].[Release] AS t1
  ) AS t0
WHERE ([t0].[ProductId] = 2)

[t0]. [c0] NumberOfInstalls. , c0 .

: if 10x , .

+1

, , ORM. , , - :

from r in Release.All()

. - , SubSonic !

, :

 var result = from r in Release.All()
              select new ReleaseInfo {
                  Release = r,
                  NumberOfInstalls = Install.All().Count(x => x.ReleaseId == r.Id)
              };

Install.All(), . , , .NET, , . .Find SubSonic, , . , - , . :

var result = from r in Release.All()
             select new ReleaseInfo {
                 Release = r,
                 NumberOfInstalls = Install.Find(x => x.ReleaseId == r.Id).Count()
             };
+1

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0

3.0.0.4? , . 2 , - , - . SS SimpleRepository, . , , . , ?

10- , . , :)

-1

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